The problem is threefold. First of all, at least in the early game, manpower should be a lesser factor, in how many troops you field. Money should make the world go around, and smallish - but rich - nations should be able to field armies the size of bigger, poorer neighbours. This would change with time, of course, but out of tiny city-states (like the Imperial Cities), everyone should be able to put 10-15k men on the field...if they have the money to pay for them. This would make so that smaller revolts are more dangerous. Then - and this is not PDS's fault, really - battles should be as a whole less random, BUT the occasional bouts of good/bad luck should REALLY change how a battle ends. A flank leader takes an arrow to the knee, falls from the horse and is trampled to death; the whole flank panics and collapses, the much smaller enemy army enters the gap and destroys the center. But they won't do this, because the screams would be heard from Mars. Lastly - and this IS PDS's fault - revolts are much more than an army popping up. The least dangerous - peasant rebellion - means making a big stretch of land empty of farmers, artisans and so on, damaging your economy; noble rebellions come with their share of attempted assassinations, palace intrigues, armies defecting and yes, their manors being disorganized and in ruin by the war's end. Rebellions should be way more dangerous that they are now, in the long term; but, as long as PDS insists that internal politics are useless, you get the Lollards having the second biggest army in Europe.
